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Written by: Carrie Gotzke and Heather Sample Gosse, University of Alberta

Vocalizing begins with the first cry. Caregivers begin the process of communication by responding to infant’s vocalizations. When caregivers respond consistently to infants’ cries, infants learn the signal-response pattern that is critically important to successful communication. Continued successful communication development depends both on the ability of the infants to signal messages clearly and the ability of their caregivers to interpret those signals. Vocal skills develop in the context of interaction with others. For more information, please refer to Interacting 0 – 3 Months.

Oral Control - The Foundation for Vocalizing

The rhythmic suck-swallow pattern, first established in utero at six months gestation, is essential to speech development (Owens, 2001). As infants develop, the suck-swallow pattern changes from up-and-down jaw movement to more lateral jaw movement a few weeks after birth and finally, to back-and-forth jaw movement by one month.

As early as two months, infants develop two distinct sucking behaviors: nutritive and nonnutritive (Owens, 2001). The objective of nutritive sucking is to acquire nutrition, whereas the objective of nonnutritive sucking may be to explore the environment or to obtain comfort. Nonnutritive sucking involves sucking on fingers and objects. Both nutritive and nonnutritive sucking behaviors help infants develop control of the muscles used to produce speech.

Crying – The Earliest Communication

Crying is the infants’ earliest communication tool for expressing their needs. Crying can be described as a series of nasalized vowels (Creaghead, Newman & Secord, 1989). Four cries have been identified: birth cry, basic cry, pain cry and temper cry (Owens, 2001). The first cry heard is the birth cry, which consists of two gasps following by a wail that lasts for about one second, with a flat, falling tone. The basic cry “consists of a rhythmic pattern of loud crying, silence, whistling inhalation and rest” (Owens, 2001, p. 75). This pattern expresses a generalized level of excitement. The pain cry is loud, shrill and followed by short whimpers and may be accompanied by clenched fists and tense facial muscles. Finally, the temper or anger cry is louder and longer with more air expended.

In addition to communicating needs, crying also serves the purpose of acclimating the infant to airflow across the vocal folds and changes in breathing patterns. The modified breathing that takes place during crying will progress to the lengthened exhalations of speech.

By the end of the first month, caregivers can determine the reason for the cry by its sound (Owens, 2001). Infants are also learning that when they cry, caregivers respond. From this stimulus-response sequence, infants learn that their behavior results in predictable outcomes and can affect their environment (Owens, 2001).

First Vocalizations

The vocalizations of infants are initially limited to reflexive sounds and crying. But by the second month, infants will be producing more speech-like vocalizations known as quasi-resonantal nuclei. Cooing, gooing and laughter follow soon after.

Reflexive Vocalizations

From birth to two months, the vocalizations of infants are primarily reflexive in nature. These reflexive vocalizations include crying and fussing and vegetative sounds like coughing and burping (Menn & Stoel-Gammon, 2005; Owens, 2001). Reflexive vocalizations are generally vowel-like and produced on exhalation, whereas vegetative sounds are more variable in terms of sound and how they are produced (Owens, 2001).

The range of vocalizations during the first two months is partially limited by the shape of infants’ vocal tract (Menn & Stoel-Gammon, 2005). In addition to having a small oral cavity that is filled with the tongue, their larynx is high in the neck, limiting the range of sounds that can be produced. With growth of the neck and head, infants become able to produce a greater variety of sounds and reflexive vocalizations decrease.

Quasi-Resonantal Nuclei

As infants age and grow, crying decreases and cooing, laughing and more speech-like sounds begin to be heard (Creaghead, Newman & Secord, 1989; Sachs, 2005). These sounds most often occur in interactions with caregivers. Initially, production of these speech-like sounds is accidental due to infants’ limited control over the vocal tract (Creaghead, Newman & Secord, 1989). These vocalizations are known as “quasi-resonantal nuclei” (Owens, 2001) and tend to sound like nasalized consonants and/or nasalized high to mid vowels. These quasi-resonantal nuclei (QRNs) are considered to be only partially resonated as infants do not open their mouths widely, have limited tongue control and do not sustain the sounds (Creaghead, Newman & Secord, 1989). Initially, QRNs consist of individual sounds but become sound sequences over time.

Gooing and Cooing

By two months of age, infants have developed sufficient oral control to stop and start movement (Owens, 2001) and to produce sounds with greater resonance (Creaghead, Newman & Secord, 1989). Sound production at this time is characterized by “gooing" or cooing and laughter. Cooing is described as a QRN in which velar or uvular closure (i.e., back of tongue contacts the palate or pharyngeal wall) is partially or completely achieved such that a back consonant (e.g., “k” and “g”) and middle to back vowel sound combination (e.g., “ooo”) is produced (Apel & Masterson, 2001; Menn & Stoel-Gammon, 2005; Owens, 2001). Consonants produced in cooing range from velar fricatives that sound similar to /s/ and velar stops similar to /k/ and /g/. Cooing can be elicited by speech, attention, and toys and signal caregivers that their infants are not in distress. Gooing and cooing are also known as comfort state vocalizations (Menn & Stoel-Gammon, 2005). As infants’ vocalizations increase, the amount of time spent crying decreases (Owens, 2001).